Systems and methods for arc and node design and manufacture

ABSTRACT

A metal extrusion and nodes based structure is provided. The structure comprises one or more arc members connected by one or more node members, wherein the arc comprises (i) a wing feature which is configured to mate with one or more non-structural components, (ii) an internal passage feature which is configured to be inserted into a connecting feature of the corresponding node member, and (iii) one or more keying features formed from a mating interface with the corresponding node member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of, and claims priority to, U.S.Non-Provisional patent application Ser. No. 15/619,326, filed on Jun. 9,2017, entitled SYSTEMS AND METHODS FOR ARC AND NODE DESIGN ANDMANUFACTURE, now pending, which claims the benefit of U.S. ProvisionalPatent Application No. 62/347,953, entitled SYSTEMS AND METHODS FOR NODEAND ARC DESIGN AND MANUFACTURE, filed on Jun. 9, 2016, all of which areexpressly incorporated by reference herein in its entirety.

BACKGROUND Field

The present disclosure relates generally to design and manufacturing ofstructures, and more particularly, to design and manufacture of metalextrusion structures.

Background

Three-dimensional (3-D) printed or additively manufactured nodes andfabricated formed arcs can be used in automobiles, structuralapplications, marine vehicles, etc. 3-D printed nodes can be used forthe connection of tubes, and the nodes may be printed according togeometric and physical requirements at each tube's intersection point.The fabricated formed arcs may be employed to accommodate variousstructural surfaces, such as A-surfaces (which are the exposed surfacesthat are seen by the consumer) and support structural load. The arc andnode structures can be used as supporting structures interfacing withnon-structural components such as the door and window of a vehicle, forexample. These structures may need to be designed to meet variousobjectives including aerodynamics, styling, visibility, safety, etc.However, traditional methods to fabricate arcs, particularly arcs thatinclude A-surfaces, may incur high equipment and manufacturing costs.

SUMMARY

In various aspects, an apparatus a structure can include a metalextrusion including a first structure and a second structure, the metalextrusion having a length, wherein the first structure includes anelongated cavity along the length of the metal extrusion, and the secondstructure includes an elongated surface along the length of the metalextrusion, the elongated surface being arranged away from the firststructure and overlapping at least a portion of the first structure, thefirst and second structures being connected along the length of themetal extrusion.

In various aspects, a vehicle can include a metal extrusion including afirst structure and a second structure, the metal extrusion having alength, wherein the first structure includes an elongated cavity alongthe length of the metal extrusion, and the second structure includes anelongated surface along the length of the metal extrusion, the elongatedsurface being arranged away from the first structure and overlapping atleast a portion of the first structure, the first and second structuresbeing connected along the length of the metal extrusion, and wherein anA-surface of the vehicle includes at least a portion of the elongatedsurface.

In various aspects, a method of manufacturing a structure can includeaccepting a metal extrusion, the metal extrusion including a firststructure and a second structure, the metal extrusion having a length,wherein the first structure includes an elongated cavity along thelength of the metal extrusion, and the second structure includes anelongated surface along the length of the metal extrusion, the elongatedsurface being arranged away from the first structure and overlapping atleast a portion of the first structure, the first and second structuresbeing connected along the length of the metal extrusion, deforming thefirst structure in a first direction, and deforming the second structurein a second direction different than the first direction.

In various aspects, a die for deforming a metal extrusion can include afirst die component that deforms a first portion of the metal extrusionin a first direction, and a second die component that deforms a secondportion of the metal extrusion in a second direction different than thefirst direction.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of will now be presented in the detailed description byway of example, and not by way of limitation, in the accompanyingdrawings, wherein:

FIG. 1 illustrates an exemplary arc structure including nodes connectedby a metal extrusion.

FIG. 2 illustrates an exemplary metal extrusion with a shape to meet aprecise geometric fit requirement.

FIG. 3 illustrates exemplary metal extrusions with elongated cavitiesand elongated surfaces.

FIG. 4 illustrates an example of a node connected to a metal extrusion.

FIG. 5 illustrates cross-sectional views of an exemplary metal extrusionwith end-cuts deformable in various directions.

FIG. 6 illustrates exemplary end-cut surfaces with various keyingfacets.

FIG. 7 illustrates an exemplary structure built on a plurality of arcsand nodes structures.

FIG. 8 illustrates an exemplary arcs and nodes assembly implemented onphysical nodes and arcs.

FIG. 9 illustrates an exemplary subassembly based on the arcs and nodesstructures.

FIG. 10 illustrates an exemplary metal extrusion and an exemplary metalextrusion with a helical twist.

FIG. 11 illustrates an exemplary extrusion deforming apparatus.

FIG. 12 illustrates more examples of a bending and twisting process.

FIG. 13 illustrates an exemplary deformation of an elongated surface.

FIGS. 14A-B illustrate an exemplary dynamic die that can deformdifferent portions of a metal extrusion in different directions.

FIG. 15 illustrates an exemplary layered dynamic die.

FIGS. 16A-F illustrate exemplary layers of a layered dynamic die.

FIG. 17 illustrates an exemplary die layer including multiple dies.

FIG. 18 is a flowchart illustrating an example method of deforming ametal extrusion in different directions.

FIG. 19 illustrates exemplary metal extrusions and nodes for a vehicleroof structure.

FIG. 20 illustrates an exemplary metal extrusion and node structureconnected to panels.

FIG. 21 illustrates an exemplary vehicle based on nodes and metalextrusions.

FIG. 22 illustrates examples of metal extrusions and nodes structuresused in a vehicle.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended to provide a description of various exemplaryembodiments of the concepts disclosed herein and is not intended torepresent the only embodiments in which the disclosure may be practiced.The term “exemplary” used in this disclosure means “serving as anexample, instance, or illustration,” and should not necessarily beconstrued as preferred or advantageous over other embodiments presentedin this disclosure. The detailed description includes specific detailsfor the purpose of providing a thorough and complete disclosure thatfully conveys the scope of the concepts to those skilled in the art.However, the disclosure may be practiced without these specific details.In some instances, well-known structures and components may be shown inblock diagram form, or omitted entirely, in order to avoid obscuring thevarious concepts presented throughout this disclosure.

This disclosure provides a metal extrusion and nodes structure andmethods for generating the structures. The methods may be involved indesign, optimization, assembly, manufacture and integration processes.The metal extrusions may be deformed into arcs, for example, and fittedto nodes to form structures that may be integrated as vehiclestructures. The arcs and nodes structures may be designed to meetvarious requirements of a vehicle including structural, shape andfunctional requirements. The nodes may be additively printed or 3-Dprinted, for example. The arcs may be configured to fit into a structureand provide a set of functions. For example, the arcs may be formed intovarious shapes to match the allocated requirements that include exteriorand interior surface shapes, including A-surfaces, attachment surfacesthat match structural sheets, and structural capacity such as loadbearing. The arcs and nodes structures can be used to serve commonvehicular functions including door sills, body and rocker panels, windowseal surfaces, wheel wells, seating rails, battery and motor supportsfor electric vehicles, and wiring harnesses, etc. Various aspects of thedescribed disclosure may be applied to applications identified herein inaddition to other structures comprising a nodes and arcs basedstructural construction. It shall be understood that different aspectsof the disclosure may be implemented individually, collectively, or incombination with each other.

FIG. 1 shows an exemplary arcs and nodes structure 101 including one ormore nodes 103, 107 connected by a metal extrusion, such as an arc 105,in accordance with an embodiment of the invention. A metal extrusion canbe formed into an arc and may be provided to connect one or more nodesto form a planar or three-dimensional structure. The arc and nodes maybe assembled to form a configuration that can mate with other componentsof a vehicle. The components can be components of vehicle with variousfunctions, structures, and shapes. The components can be structuralcomponents such as similar arc and node structures, joints, tubes,vehicle chassis, vehicle frames, vehicle bodies, etc. The components canbe vehicle components that have complex shapes such as door panels, roofpanels, floor panels, or any other panels forming the vehicle enclosure.The components can be non-structural components that have variousfunctions, such as door sills, body and rocker panels, window sealsurfaces, wheel wells, seating rails, battery and motor supports forelectric vehicles, wiring harnesses, etc. Greater details about arc andnodes structures designed and manufactured to meet the structural, shapeand functional requirements will be discussed later herein.

The formed configuration of the arc and nodes structure 101 may have anexternal outline that can fit into a designed object such as a vehicle.For example, a vehicle may have an external and/or internal form orshape whose outline is determined by a large number of requirementsincluding functionality, aerodynamics, styling, and manufacturability.Such shape requirement may be applied to the design of the arc and nodestructures such that they can conform to the complex shaped body parts.The configuration of the arc and nodes structure 101 may be formed basedon the shape and structure of the arc and each individual node, and theconnection configuration between the node and the corresponding arc end.For instance, the linear shape of the arc 105 may follow apre-determined arch that may be curved, twisted, or bent helically toconform to a specific shape and functions. The shape and structuredesign of the arc is described later herein.

The arc 105 may be connected with one or more nodes or joints 103, 107in a specific position and orientation. The connection may be guided andreinforced by a purpose-built connection shape of nodes andcorresponding arc ends. For instance, the node 103 is mated with the arc105 at the left end in a specific position and orientation, and likewisethe node 107 is mated with the arc 105 at the right end in a positionand orientation that may or may not be the same to the left endconnection. The connection between the arc and node may impart rigidity,structural and torsional strength, and constitute a precise object shapeto serve certain useful purposes.

In various embodiments, the connecting arc 105 may be formed fromplastic, metal, carbon fiber material, or any other available compositematerial. Examples of composite materials may include high moduluscarbon fiber composite, high strength carbon fiber composite, plainweave carbon fiber composite, harness satin weave carbon composite, lowmodulus carbon fiber composite, or low strength carbon fiber composite.In some embodiments, the arcs may be formed from other materials, suchas plastics, polymers, metals, or metal alloys. The connecting arcs maybe formed from rigid materials. The connecting arcs may be formed of oneor more metal and/or non-metal materials.

The connecting arcs may be fabricated as designed. Any fabricationtechnique may be used for the connecting arcs, including but not limitedto, extrusion, bending, twisting, stamping, molding, rolling, forging,drawing, molding, CNC machining, 3-D printing, braiding, composites,lithography, welding, milling, extrusion, molding, casting, or any othertechnique or combinations thereof. The connecting arcs may have varyingdimensions. For example, different connecting arcs may have differentlengths.

The connecting arcs may have different cross-sectional shapes. Forexample, the connecting arcs may have a substantially circular shape,square shape, oval shape, hexagonal shape, or irregular shape. Theconnecting arcs cross-section could include an open cross section, suchas a C-channel, D-channel, I-beam, or angle. Details regarding the shapeof various exemplary arcs are described later herein.

The connecting arc 105 may include an elongated cavity, such as a hollowtube. A hollow portion may be provided along the entire length of thetube. For example, the connecting arc may have an inner surface and anouter surface. An inner diameter for the tube may correspond to an innersurface of the connecting tube. An outer diameter of the tube maycorrespond to an outer surface of the tube. A connecting arc may havetwo ends. The two ends may be opposing one another. In some embodiments,the connecting tubes and nodes may have three, four, five, six or moreends. The vehicle chassis frame may comprise carbon fiber tubesconnected with nodes.

The nodes 103, 107 (a.k.a. joints, joint members, joints, connectors,lugs) presented in this disclosure may be suitable for use in a vehiclechassis frame and body. The node may be multi-port. The nodes may bedesigned to fit the arc angles dictated by the chassis design. A singlenode may connect to both arcs and straight tubes. The nodes may bepre-formed to desired geometries to permit rapid and low cost assemblyof the chassis. In some embodiments the nodes may be pre-formed using3-D printing techniques. 3-D printing may permit the nodes to be formedin a wide array of geometries that may accommodate different frameconfigurations. 3-D printing may permit the nodes to be formed based ona computer generated design file that comprises dimensions of the nodes.

A node may be composed of a metallic material (e.g. aluminum, titanium,or stainless steel, brass, copper, chromoly steel, or iron), a compositematerial (e.g. carbon fiber), a polymeric material (e.g. plastic), orsome combination of these materials. The node can be formed from apowder material. The nodes may be formed of one or more metal and/ornon-metal materials. The 3-D printer can melt and/or sinter at least aportion of the powder material to form the node. The node may be formedof a substantially rigid material.

A node may support stress applied at or near the node. The node maysupport compression, tension, torsion, shear stresses or somecombination of these stress types. The type, direction, and magnitude ofstress may be static and dependent on the location of the node in astructure. Alternately the stress type, direction, and magnitude may bedynamic and a function of the dynamics of the structure, for example thestress on the node may change as the vehicle structure climbs ordescends a hill.

The nodes or joints may be fabricated as designed. Different fabricationtechniques may be used for the nodes or joints, including but notlimited to, 3-D printing, braiding, composites, lithography, welding,milling, extrusion, molding, casting, or any other technique orcombinations thereof.

FIG. 2 illustrates an example of a metal extrusion, e.g., an arc,designed to meet a geometric requirement, in accordance with someembodiments. A metal extrusion may be designed to conform to a form orshape of a portion of a vehicle. The form or shape may be dictated by anumber of requirements including functionality, aerodynamics, styling,and manufacturability. In some embodiments, the arc members may havecomplex shapes and curves in order to conform to a shape requirementsuch as forming door components and window support. In some embodiments,the shape requirements may require the arc to conform to various shapessuch as a curved, arch, linear, non-linear and the like that may becurved on one or more planes.

In some embodiments, one or more non-structural components such asdoors, windows, panels of a vehicle body may be attached to a body framevia an arc and node structure. The non-structural components may havecomplex shapes. The arc and node structure may be required to provideboth structural support to the components while meet shape requirementby fitting with the components. In some embodiments, the arcs may bedesigned to fit with edges, facets, interfaces or any possible contactportion of the components.

FIG. 2 shows an example of a metal extrusion, such as an arc 205, with ashape to meet a precise geometric fit requirement. As shown in the firstview of a window structure, arc 205 is formed to have a shape followsthe edge of a domed glass window 201. The glass window 201 has avariable compound curve that may change along the length. The windowglass 201 may be shaped to form a dome that provides an aerodynamicsurface for the exterior of the vehicle. The glass may requirestructural support that can be provided by arc 205. The arc as shown inthe example has a shape at least in longitude dimension substantiallyadapting to the shape of the glass window. In some embodiments, an edge,surface, width, length or any other geometric dimension of an arc may bedesigned in order to fit with a contacting portion of other components.

In some embodiments, additional elements may be included between an arcand the non-structural components such as the window glass. In thewindow structure example, an elastomeric seal 203 may be provided toallow a hermetic interface between the glass window 201 and arc 205. Theelastomeric seal 203 may further provide compliance or shock absorptionfor vibration and dynamic forces as well as adhesion between surfaces.In other examples, an arc may be configured to directly contact oradhere to a portion of vehicle body components with or withoutadditional elements.

In some embodiments, a metal extrusion, such as an arc, may have acompound shape. As illustrated in an underside view B of the same windowstructure in FIG. 2, a metal extrusion can include a structure that hasan elongated surface, such as a wing feature, along the length, whichmay be mated with other components of a vehicle such as the glass window201. In this window structure example, the wing feature may have aninterface connect with the glass window 201 through a seal element 203.The metal extrusion may also include an elongated cavity that forms aninternal passage that may have various cross-sections, such as a D-shapeas shown in the figure. The arc member may be twisted and bent along thelength in order to follow the dome shape of the glass window, forexample.

FIG. 3 shows examples of the arc member with conduit and wing features,in accordance with various embodiments. The arc members 310, 320 mayhave various shapes to fit into a vehicle structure. The geometry shapeof the arc members may be formed to mate with one or more structural ornon-structural components of the vehicle. For instance, thecross-section interface and the inner shape of the arc members may beformed in order to accept one or more node members that may or may notbe part of a main frame of the vehicle. The external outline of the arcmembers may be formed to mate with components such as panels, doors,windows, and the like. Further, one or more features of the arc membersmay provide additional functionalities that need not be structural. Forinstance, the arc members may be formed with conduit or internalpassageway for electrical and/or fluid passages. In another instance,the arc members may be formed with keying features to provide a uniqueassembly configuration of an arc and nodes structure.

In some embodiments, the arc members may include elongated cavities thatmay, for example, form conduit or internal passageway, such as elongatedcavities 313, 323. The conduit or passageway features may be used forvarious purposes. For example, the conduit features may enclose andprotect an electrical wiring harness, or provide a passageway or storagecompartment for fluid, fuel, or air. Examples of fluid passageways mayinclude coolant, lubrication, ventilation, air conditioning, and/orheating ducts. The electrical wiring may be used to provide or transmitpower to systems on board a vehicle and/or to provide power to a batteryto start or run the vehicle engine. Systems on board a vehicle that usepower from the arcs and nodes structures may include, navigation, audio,video display, power windows, or power seat adjustment. Powerdistribution within a vehicle may travel through a arcs and nodesstructures. Other examples of electrical system that may requireelectrical routing from a source to a system may include audio systems,interior lighting systems, exterior lighting systems, engine ignitioncomponents, on board navigation systems, and control systems.

Each tubular arc may include one or more conduits or passageways alongits length. The tubular arc may comprise a single conduit with variouscross-sections that need not be closed shape, such as an oval shape,circular shape, D shape, and C shape, etc. Each tubular arc may comprisemultiple conduits by including one or more compartments along thelength. Each tubular arc may be configured to provide electrical, fluid,air passageways individually or collectively.

The tubular cross-section of the arc may provide structural support inaddition to the functionalities as described previously. The structureof the arc may be provided to stabilize the geometric positions of thenodes to which it connects. The structure of the arc also providesphysical strength and mutually-reinforcing load-bearing capability byadding strength and geometric stability along the length of the arc. Thetubular arc may have improved resistance to bending and twisting. Thetubular arc may support stress applied at the arc. The tubular arc maysupport compression, tension, torsion, shear stresses or any combinationof these stress types. The type, direction, and magnitude of stress maybe static and dependent on the location of the arc in a vehiclestructure. Alternately the stress type, direction, and magnitude may bedynamic and a function of the movement of the vehicle, for example thestress on the arc may change as the vehicle having variable vibrationsand accelerations.

As mentioned previously, the tubular arcs may have various differentcross-sections. The tubular arcs may have an inner surface and an outersurface that forms a hollow portion. The hollow portion may be providedalong the entire length of the tube or a portion of the length. An innerdiameter for the tubular arcs may correspond to an inner surface of theconnecting tubular arcs. An outer diameter of the tubular arcs maycorrespond to an outer surface of the tubular arcs. A connecting arc mayhave two ends. The two ends may be opposing one another. In alternativeembodiments, the connecting nodes may have three, four, five, six ormore ends. The two or more ends of the arc may or may not have the samegeometric dimensions. In some embodiments, the shape of the arc may bepolarized and asymmetrical with dissimilar ends.

As shown in FIG. 3, the arc member 310, 320 may also include a structurewith an elongated surface, such as a wing feature 311, 321. The wingfeature 311, 321 may be protrusions projected to two sides of the arcmember, thus overlapping the elongated cavities 313, 323. The wingfeatures may be connected to the elongated cavities 313, 323.

In particular, elongated cavity 313 can include longitudinal edges 331defining an opening 333 in a wall of the elongated cavity. The openingcan run along a length of elongated cavity 313. Arc member 310 caninclude a support structure 335 that connects the longitudinal edges towing feature 311. In various embodiments, the support structure may beconfigured to deform in response to a bending wing feature 311,elongated cavity 313, or both, such that the deformation of the supportstructure relieves a mechanical stress within the arc member 410 thatresults from the bending.

As shown in FIG. 3, wing features 311, 321 can include a plate. The wingfeature need not have the same thickness as the tubular body of the arcmember. The wing feature may have various curvatures or geometrics. Forexample, the wing feature may be a substantially flat top of the arcmember. The wing feature may have a domed or arched shape. The wingfeature needs not have a smooth surface. In some embodiments, the wingfeature may be formed with additional features such as steps as shown inthe figure to accept other components of a vehicle. The wing featureneeds not be symmetrical. For instance, the left side and right side ofthe wing feature may have different width, thickness, outlines, and/orcurvatures. In another instance, both sides may have the same finefeatures (e.g., grooves, steps, channels, etc.), or either side may havethe fine features. In various embodiments, the wing feature may includean elongated surface 350, 351 that serves as an A-surface of a vehicle.

In some embodiments, the wing features may provide interface functionsto other components. For this purpose, the wing features may adopt ashape in order to mate with the shape of other components. The wingfeature may have various shapes to conform to any complex shapes such asthe domed glass window in FIG. 2. The dimension of the wing feature andthe formed features (e.g., steps) may be determined based on the shapeof the components. For instance, the dimension of the step features maybe designed to provide an interface to another component such that thestep features may follow the contact surface of the interfacingcomponent and a smooth external surface may be formed. In anotherinstance, the dimension of the top surface of the wing feature may bedesigned to meet external shape requirement of a vehicle such that thewing feature may provide a smooth transition, a smooth external outlineor a sharp corner as desired.

The wing feature of the arc member may be connected with othercomponents via various means. The connecting means may be selected basedon the materials of the components, shape, coupling strength and/orassembly requirements, etc. In examples, the wing feature may beconnected to the components via mechanical fastening means. Fasteners,such as screws, bolts, nuts, rivets, interlocks, or clamps may be used.The fastening between the arc and the mating components may permit thecoupled structure to be relatively fastened to one another. The one ormore fasteners may be removable. The one or more fasteners may or maynot permit a relative movement between the coupled components. Thefasteners may facilitate disassembly of the one or more components fromthe arc member as needed. For instance, one or more fasteners may permitthe one or more components (e.g., windows, panels, sills) to beremovable by unfastening the arc member.

In other examples, the wing feature of the arc member may be bond toother components using adhesives, welding, or any suitable bondingtechniques. The bonding means may be selected based on the types ofmaterial of the components and the arc member at the bonding interface.The components to be bond to the arc member may be formed from acombination of different types of materials, such as a compositematerial (e.g., carbon fibers), a metal material (e.g. aluminum,titanium, or stainless steel, brass, copper, chromoly steel, iron, othermetal materials, or an alloy formed therefrom), a polymeric material(e.g., plastic, rubber), a glass or combinations thereof. The componentsmay be rigid or elastic. The adhesives/glues used may cause physical orchemical bonding formed at the interface. The bonding techniques may beselected to provide a desired bonding strength. In some embodiments,bonding may be formed without additional adhesives or glues. Forinstance, the components may be composed of material that may be capableto bond to the arc members under certain conditions such as heat,pressure, or catalyst, etc.

One or more arc members may be provided to connect with two or morenodes to form an arc and nodes structure. FIG. 4 shows an example of anode 410 connected to a metal extrusion, such as an arc 420, inaccordance with embodiments. In some embodiments, the node 410 may beadditively manufactured or 3-D printed node. The node can be the samenodes 103, 107 as described in FIG. 1.

In some embodiments, the node 410 may be multi-port. In someembodiments, the node may be single port. The node may be designed tofit the arc angles dictated by the chassis design. A single node may beconnected to different arcs and tubes. The nodes may be pre-formed todesired geometries to permit rapid and low cost assembly of the chassis.In some embodiments, the nodes may be pre-formed using 3-D printingtechniques. 3-D printing may permit the nodes to be formed in a widearray of geometries that may accommodate different frame configurations.3-D printing may permit the nodes to be formed based on a computergenerated design file that comprises dimensions of the nodes.

The node 410 may support various types of stress as described elsewhereherein. The node may be fabricated from a single integral piece ofmetallic material (e.g. aluminum, titanium, or stainless steel, brass,copper, chromoly steel, or iron), a composite material (e.g. carbonfiber), or a polymeric material (e.g. plastic). The material andstructures of the nodes may be designed to meet the structuralrequirements. The nodes may be smart nodes embedded with sensors. Thenodes may have various features such as centering features and internalpassageways.

In some embodiments, the nodes may be shaped to accept the arc and oncethe node and arc mated together, they are fastened into a singleassembly. For instance, a node may be glued to an end of arc at oneacceptor port and glued to another tube or arc at another acceptor port.The node can comprise one or more integrated structural featuresconfigured to provide a fluid pathway for delivery of adhesive from anadhesive source to a connection point or space between the node and thearc. In some cases, the adhesive can be simultaneously pushed into thespace between the node and the arc with positive pressure through anadhesive injection port and pulled into the space by a negative pressuresource applied to the space. The node can be heated in order tofacilitate flow of the adhesive within the one or more integratedstructural features to reduce cycle time and accelerate curing.

When using adhesives to attach the one or more arcs to the nodes, it canreduce the overall weight of the vehicle. However, when a certain partof the vehicle needs to be replaced due to a crash or a componentfailure, it may be difficult to replace the certain part only withoutabandoning the entire structure, or to remove the certain part alone.Using a technique where node components are attached to one another withaid of one or more fasteners may facilitate disassembly of the vehiclechassis as needed. For instance, one or more fasteners may permit thenode components to be removable relative to one another by unfasteningthe node components. Then, the portion of the vehicle chassis that needsto be replaced can be swapped in for a new piece that can be fastened tothe existing vehicle chassis structure. For example, when a certain partof the vehicle needs to be replaced, the corresponding arcs and nodesmay be easily disassembled, and a new replacement part may be fastened(e.g., bolted, screwed, riveted, clamped, interlocked) to the originalstructure. This may provide a wide range of flexibility, and theportions of the vehicle chassis may range from a single piece to wholesections of the vehicle. For instance, if a section of a vehiclecrumpled on impact, the entire section may be disassembled from thevehicle chassis and replaced with a new section which is undamaged. Insome instances, such section of a vehicle may be functional structuresuch as a window structure, a roof structure, a door structure, or astructural module such as a chassis module, a chassis sub-structure, achassis sub-assembly, or any other part of a vehicle as discussedherein. The new section may be pre-assembled and then attached to thevehicle chassis at the connection points, or may be assembled piecemealon the existing vehicle chassis and body. Such flexibility may alsoallow easy upgrades or modifications to the vehicle. For instance, if anew feature is possible for the vehicle body (e.g., window, roof panel,etc), much of the original chassis can be retained while the new featureis installed on the vehicle.

The nodes may have internal features that may provide fluid andelectrical passageways. The internal passageways of the nodes may beconnected to the internal passageways of the arcs to form a network. Insome embodiments, the shape of the nodes may be designed to fit thegeometric dimension of the connected arc in order to form a connectedpassageway.

In some embodiments, the node 410 may comprise extrusion features 411similar to the wing features of the arcs. The extrusion features may bedesigned to conform to the shape requirement of the vehicle structure.The extrusion features may be geometrically fit with the connected arcsand other components. The extrusion features may provide a uniqueinterface to the mating part of a keying features as described laterherein. An outer surface of the extrusion feature may form a smoothexternal surface together with the wing feature of the arc and theconnected other components.

In the example as shown in FIG. 4, the node 410 is formed withconnecting feature 401 designed to mate with the arc 420. The nodes maybe shaped to connect with a mating arc in a specific pose. Theconnecting feature may be a mating socket that is provided to plug inand accept the arc. In some embodiments, the nodes may form a femaleside of the connection whereas the mating arc forms a male side. In thiscase, an inner surface of the node may mate with an outer surface of thearc end. In other embodiments, the nodes may form a male side and themating arc may form a female side. In this case, the inner surface ofthe end of the arc conduit may mate with the outer surface of theconnecting feature of the node. As shown in the figure, the node 410contains a D-shaped male connector 401. The arc 420 includes a D-shapedinternal passageway 403 that fits precisely over an outer surface of themale connector. The mated node and arc 420 is illustrated in the figure.

In some embodiments, the interface of the mating node and arc mayinclude one or more contacting surfaces and edges. The mating interfacemay include, for example, an outer surface of the connecting feature ofthe node, an inner surface of the mated end of the arc conduit, and aninterface where the wing features of the arc and node meet 431. In someembodiments, the interface 431 needs not be normal to a longitude axisof the arc. In some embodiments, the interface 431 needs not be parallelto the end surface of the connecting feature of the node. In someembodiments, the corresponding surfaces and/or edges at the matinginterface may have complimentary shapes or features. Adhesives orsuitable bonding techniques may be applied to the interfaces of themating nodes and arcs. Adhesives or suitable bonding techniques may beapplied to the side walls between the mating nodes and arcs.

In some embodiments, the node and arc may be mated together in a singleorientation. For example, the anisotropic D-shape connecting feature ofthe node and the corresponding D-shape conduit of the arc may ensure asingle mating orientation of the arc and node structure. The formedshape may lock the node and arc in terms of a rotational movement aboutan axis of the arc. It should be noted that various shapes may providesuch locking function, such as triangular, rectangular, oval, polarized,and the like that. In other embodiments, when a relative movementbetween the node and arc is desired like a rotation about the arc axis,a substantially circular shape of the connecting feature and conduit maybe adopted.

In some embodiments, the arcs and nodes structure may comprise keyingfeatures to provide unique assembly of the structure. For example, thenode 410 may have a keyed mating surface that uniquely mates with thejoining arc 420 that has the complimentary keying features. Theuniqueness mating may be applied to a single joining end such that onlyone end of the arc can mate with a specific connecting feature of thenode. The uniqueness mating may be applied to a single set of node andarc such that only the arc can mate with the mating node but fit with noother nodes.

The property of uniqueness can discretionally be designed into eachindividual node-arc joint in a structure or across a number ofstructures. Each node connecting feature and its mating arc end can bematched or keyed as a unique pair. In some embodiments, the uniquematching or keying may make each join unique within a node and arcstructure, between node and arc structures, or between any subassembliesand assemblies.

The keying features may be mechanically-enforced compatibility. Thekeying features may have the beneficial effect of eliminating thepossibility of errors during structure assembly and manufacturing. Forinstance, if the structural components (e.g., nodes and arcs) fitstogether and successfully matched, then it cannot contain assemblyerrors. In some cases, when a plurality of parts and components havesimilar shapes and structures (e.g., similar ends of an arc, similararcs, similar nodes, etc), the uniqueness property of the providedinvention allows the structures built on nodes and arcs assembledtogether correctly.

The uniqueness property or keying property may be used to defineuniversal standards and provide a class of compatibilities. The classesand stands may be defined within a product, within a class of products,or within a factory. For instance, the nodes and metal extrusionsstructures may have keying features that are unique to a product, aclass of products, a subassembly of a product, a subassembly across aclass of products, or all the products from a factory.

The uniqueness property or keying property may be used to definemodularity of a product and commonality of parts. The modularity orcommonality may be defined by the levels of the uniqueness property. Forinstance, at a vehicle level, parts with the same keying features may beinterchangeable. The uniqueness property or keying property may be usedto defeat counterfeits. For instance, parts fabricated by an authorizedfactory may share the same keying features. The uniqueness property orkeying property may be used to prevent errors made during factoryassembly and field maintenance replacement.

The keying features may include various properties at a keying interfacebetween the node and the mated metal extrusion. The various features mayinclude the size, shape, cross sectional angle, or any othercomplimentary pairing features at the interface.

In some embodiments, the keying features may include a uniquecomplimentary shape of the connecting feature of a node and the conduitof the mating end of the metal extrusion. For instance, as describedpreviously, the geometric fit between the connecting feature 401 of thenode 410 and the conduit 403 at the mating end of the metal extrusion420 provides a keying feature such that the node 410 may not fit withother metal extrusions. Moreover, the unique shape at the mating end ofthe metal extrusion may ensure that only the single end of the metalextrusion can fit into this port on the node to prevent assembly of thewrong end.

The keying features may include any features at the interface of thenode and mated metal extrusion. In some embodiments, an angle of themating interface with respect to an extrusion axis of the metalextrusion may be provided as a keying feature. The mating interface maybe the plane where an end-cut surface of the formed metal extrusion andthe corresponding port of the 3D-printed node meet, such as theinterface 431 in FIG. 4.

FIG. 5 shows examples of the metal extrusions with end-cut plane ofvarious orientations served as keying features, in accordance withembodiments of the invention. The metal extrusion may be trimmed to thedesired length. The end-cut plane may be trimmed at various angles ororientations. For example, the metal extrusion as illustrated inscenario A has an end-cut plane normal to an extrusion axis of the metalextrusion. The metal extrusion as shown in scenario B may have anend-cut plane inclined about a pitch axis 503 by an angle 501. The metalextrusion as shown in scenario C may have an end-cut plane inclinedabout a yaw axis 507 by an angle 505. The inclination axes 503, 505 andinclined degree 501, 505 together defined an orientation of the end-cutplane.

The end-cut plane may be inclined in any direction or about any axis.The inclination degree with respect to a plane normal to extrusion axiscan vary in a wide range such as from −85° to +85°. The combination ofthe inclined direction and degree may provide a unique keying facet ofthe metal extrusion that can only match with the mating node port withthe complimentary keying facet.

In some embodiments, the keying facet may be single facet. In someembodiments, the keying facet may include two or more facets. FIG. 6shows examples of end-cut surface having various keying facets, inaccordance with embodiments.

In some embodiments, the metal extrusion may be formed by extrusion of afeedstock 601. One or more ends of the metal extrusion may be trimmed toform an end-cut plane. Different angle and different inclination of theend-cut plane may provide a unique keying feature. For example, themetal extrusion 620 may have an end-cut plane 621 trimmed at a specificangle and orientation such that a keying facet 621 is provided. Themetal extrusion 630 may have an end-cut plane 631 trimmed at a differentangle and orientation, such that a different keying facet 631 isprovided. The metal extrusion 640 may have an end-cut facet 641including dual facets, such that a keying facet including dual facets isprovided. In some embodiments, the keying facet 641 may be formed by acombination of the trimming operations applied to the metal extrusion620 and the metal extrusion 630. The pointed nose of the resulting Vshape represents a ridge line of the dual mating facets. The dual facetscan be formed by a first cut 621 followed by a second cut 631. Anynumber of cuttings may be performed to create any number of facets, suchas one, two, three, four, five, etc, facets. The cutting direction maybe any orientation. Accordingly the cutting facet may be inclined,tilted, rotated about an axis about any direction. The example asillustrated in FIG. 6 shows the dual facet 641 formed by two cuttingsperpendicular to the paper. It should be noted that the cuttings neednot be perpendicular to the paper plane.

The keying facet may be formed by one or more cutting operations. Theone or more cutting operation may create one or more cutting facets. Themultiple cutting facets may be formed by cutting operations along thesame direction such as the dual facets formed in FIG. 6. The multiplecutting facets may be formed by cutting operations along differentdirections for example a pyramid shaped surface. Any suitable machiningtool may be used to perform the cutting to the metal extrusion. Thecomplimentary keying facets of the nodes may be formed by 3D printing oradditive manufacture.

In some embodiments, the inclination or number of facets of the matingfacet may affect the bonding strength at the node and metal extrusionconnection. The inclined mating surface or multi-facets surface mayprovide increased contact interface between the mated metal extrusionand node. In some embodiments, the increased contacting surface mayprovide greater bonding strength. For example, the contact area betweenthe node and the metal extrusion may be increased with respect to theinclination angle, and the surface adhesion and joint strength may beimproved accordingly. Similarly, the dual or multi-facets of the matingsurface may also increase the contacting surface thus improve thebonding strength at the connecting end of the metal extrusion and node.Accordingly, the present invention provides a method of adjusting thebonding strength by altering the mating surface of the node and matedmetal extrusion.

The metal extrusions and nodes structure may be integrated with otherstructures to form a higher level structure. In examples, the higherlevel structure may be a structure or a substructure of a vehicle. Thehigher level structure built on the metal extrusions and nodes structuremay benefit from the flexibility and various characteristics of themetal extrusions and nodes structure. The metal extrusions and nodesbased structure may be allowed to meet shape and structural requirementsthat are difficult to meet with conventional structures.

FIG. 7 illustrates an example of a structure 700 built on a plurality ofmetal extrusions and nodes structures. The structure 700 may be anabstract graphical structure for illustrative purpose. The structure 700contains a plurality of nodes and metal extrusions structures that areconnected with each other. Each metal extrusion 705 may connect two ormore nodes 703. In some cases, a node may be connected with two or moremetal extrusions. For example, node 703 is connected with three metalextrusions. The geometry of the metal extrusions and the location of thenodes together formed an overall shape of the structure 700. The metalextrusion and nodes based structure 700 may have various topologies. Thestructure 700 is illustrated as a circular structure, however, alteringthe geometrics of the metal extrusions, location of the nodes, and/orconfigurations of the fundamental node and metal extrusion structure maycause variable topology of the structure.

The metal extrusion and nodes based structure 700 is structural stable.In some embodiments, the steady structure of a fundamental arcs andnodes assembly ensures a stable higher level structure. FIG. 8 shows andexample of a fundamental arcs and nodes assembly 810 implemented onphysical nodes and arcs 830, in accordance with embodiments of theinvention. The arcs and nodes assembly may be a building block used inthe structure 700. A metal extrusion and nodes assembly can be the samearcs and nodes structure as described in FIG. 1. In the example, thearcs and nodes assembly 810 comprises three nodes 811, 815,819 and threearcs 813, 817, 821. The arcs and nodes assembly 810 forms a triangularshape. In some embodiments, the structure of the arcs and nodes assemblymay be planer or two-dimensional with the three nodes defining the apexof the triangle. In this case, all the nodes and arcs form aconfiguration in the same plane. Alternatively, the structure of thearcs and nodes assembly may be three-dimensional. In this case, the arcsmay have shapes that are not coplanar with the plane defined by thethree nodes, such as bending out of the plane.

The arcs and nodes structure is embodied by a plurality of physicalparts 830 as shown in FIG. 8. The three nodes 811, 815, 819 maycorrespond to the three additively fabricated or 3D-printed nodes 831,835, 839. The three arcs 813, 817, 821 may correspond to the threefabricated formed arcs 833, 837, 841. The three nodes are connected bythe three arcs to form a triangular structure 830 correspond to thestructure 810. The arcs may or may not be different from each other. Thearcs may have different lengths, curvatures, shapes, widths, or anygeometric properties. In some embodiments, the arcs may have uniquekeying features that each arc may be assembled in a unique configurationand position. The arcs may or may not be made of the same material. Thenodes may or may not be different from each other. The nodes may bedifferent in terms of port number, size, shape, material, and anystructural properties. The nodes and arcs may have keying features suchthat the arcs and nodes may not be interchangeable within the structure.In some embodiments, the arcs and nodes may be assembled in a uniqueconfiguration such that each arc may have pre-determined mating nodes ina pre-determined orientation. For instance, arc 833 may have keyingfeatures such that it can be connected only with nodes 835 at the rightend and node 831 at the left end. In another instance, the arc 833 mayhave keying features allowing it to switch the ends such that both endsof the arc may fit into the nodes 831, 835. Alternatively, the keyingfeatures may allow one or more arcs and/or nodes interchangeable. Forexample, arc 841 and arc 839 may be interchangeable such that they canswitch positions. The node may be multi-port as described previously.The node may be designed and manufactured to accept additional arcs notshown in the figure. The additional ports of the node may allow the arcsand nodes structure 830 integrated with or assembled with other framestructures, such as beams or tubes in a vehicle space frame. Asmentioned previously, the arcs and nodes may comprise features to matewith or coupled to other structural or non-structural components, suchas brackets for machinery, fuel tanks, electronic equipment, glasspanels, sills, doors, and various other vehicular components.

In some embodiments, a subassembly built on the arcs and nodes structuremay be provided. The subassembly may be a three-dimensional structure.The subassembly may be structural reliable and stable. All theproperties and characteristics of the arcs and nodes structure can beapplied to the subassembly.

The subassembly may have resistance to certain structural failure. FIG.9 shows an exemplary subassembly based on the arcs and nodes structures,in accordance with embodiments. The arcs and nodes based subassembly maycomprise any number of nodes and any number of arcs. The subassembly mayhave any topology and configuration. For example, as shown in scenario Aof FIG. 9, the subassembly 910 comprises four nodes connected by sixarcs. In the example, the subassembly may be formed based on the arcsand nodes structure described in FIG. 8. The triangular structurecomposed by arcs 916, 918,920 and nodes 911,913,915 may correspond tothe arcs and nodes structure 810 in FIG. 8. A fourth node 917 may belocated out of the plane defined by the three nodes 911,913,915. Thefour nodes along with the six arcs form a three-dimensional pyramidtopology.

In some embodiments, the three-dimensional structure 910 adds amechanical redundancy to the fundamental arcs and nodes structure. Forexample, if any one node or arc weakens or fails, the remaining threenodes along with the remaining arcs are still connected to providestructural and various functionalities. For instance, if the node 911 isweaken, the remaining nodes 917, 913, 915 and arcs 914, 916, 922 arestill connected thus functions as a normal nodes and arcs structure.

In some embodiments, the robustness of the structure may be improved byincreasing the redundancies. Two or more arcs may be used to connect twonodes. For example, two or more arcs may be used to connect nodes 911and 917 in addition to the arc 912. In this way, if any one or more ofthe connecting arcs between the nodes 911 and 917 fail, the structuremay be still connected and reliable.

The three-dimensional subassembly is embodied by fabricated formed arcsand additively manufactured nodes as shown in scenario B of FIG. 9. Asshown in the figure, each node comprises at least three ports to connectwith arcs. The nodes 931, 937, 933, 935 may correspond to the nodes 911,917,913, 915 respectively. The arcs 932, 934, 942, 936, 938, 940 maycorrespond to arcs 912, 914,922,916,918,920 respectively. The arcs mayor may not be different from each other. The arcs within the subassembly930 may have different lengths, curvatures, shapes, widths, or anygeometric properties. In some embodiments, the arcs may have uniquekeying features such that each arc may be assembled together in a uniqueconfiguration and position. The arcs may or may not be made of the samematerial. The nodes may or may not be different from each other. Thenodes may be different in terms of port number, size, shape, material,and any structural properties. The nodes and arcs may have keyingfeatures such that the arcs and nodes may not be interchangeable withinthe subassembly. In some embodiments, the arcs and nodes may beassembled in a unique configuration such that each arc may havepre-determined mating nodes in a pre-determined orientation. Forinstance, arc 932 may have keying features such that it can be connectedonly with nodes 937 at the right end and node 935 at the left end. Inanother instance, the arc 932 may have keying features allowing it toswitch the ends such that both ends of the arc may fit into the nodes935, 937. Alternatively, the keying features may allow one or more arcsand/or nodes interchangeable. For example, arc 934 and arc 942 may beinterchangeable such that they can switch positions. The node may bemulti-port as described previously. The node may be designed andmanufactured to accept additional arcs not shown in the figure. Theadditional ports of the node may allow the arcs and nodes structure 930integrated with or assembled with other frame structures, such as beamsor tubes in a vehicle space frame. As mentioned previously, the arcs andnodes may comprise features to mate with or coupled to other structuralor non-structural components, such as brackets for machinery, fueltanks, electronic equipment, glass panels, sills, doors, and variousother vehicular components. The subassembly may be designed to providestructural support to the various components as well as conform to theshape of the components coupled to it.

In some embodiments, the design of each individual node, arc and thearcs and nodes structure may be determined/defined by a designer and/ora user based on one's design/performance need from a vehicle. Variousfactors may be considered such as functionality, aerodynamics, styling,and manufacturability, etc. In some embodiments, an individual arcmember may be designed taking into account manufacturing process, e.g.,an individual stage, an individual step, a type oftool/equipment/machine used during manufacturing. Alternatively or incombination, an individual arc member may be designed based on variousconsiderations of assembly. For example, certain nodes, connectors,and/or panels may be assembled together to form a certain chassismodule, functional structure at a site of assembly.

The arc members may be fabricated or formed. Any fabrication techniquemay be used for the connector, including but not limited to, extrusion,bending, cutting, stamping, rolling, forging, drawing, molding, CNCmachining, 3-D printing, braiding, composites, lithography, welding,milling, extrusion, molding, casting, or any other technique orcombinations thereof. In some embodiments, the manufacturing process forthe arc members may include extrusion, bending, twisting, cutting, etc.

In some embodiments, the arcs may be formed from an original piece offeedstock and shaped into the designed structure. In some cases, theoriginal feedstock may be formed into a prismatic and linear arc, thenbent and/or twisted to meet various shape requirements as describedelsewhere herein. In some embodiments, the prismatic or linear arc maybe fabricated by linear extrusion process and the various bending andtwisting may be performed by deformation process such as a tube and pipebending process.

FIG. 10 illustrates exemplary linear extruded arc 1001 and a metalextrusion with helical twist 1011, in accordance with embodiments. Thearc 1001 may be formed from a prismatic linear extrusion process. Insome embodiments, the prismatic linear arc 1001 may have a constantcross-section. The shape of the prismatic linear arc may be formedduring the extrusion process. The prismatic linear arc 1001 may befurther bent and/or twisted to form into a desired shape.

The extrusion manufacturing may be known to those skilled in the art.The extrusion may be performed at any suitable temperature, such as hotextrusion, warm extrusion, or cold extrusion. The feedstock material mayor may not be heated during the process. The shape of the extrusion diemay be designed in order to form the arc with desired cross-sections.

The feedstock material may include but not limited to plastics,polymers, metals, composite or metal alloys. The arc may be formed froma carbon fiber material, or any other available composite material.Examples of composite materials may include high modulus carbon fibercomposite, high strength carbon fiber composite, plain weave carbonfiber composite, harness satin weave carbon composite, low moduluscarbon fiber composite, or low strength carbon fiber composite. The arcmay be formed from metal or metal alloys, such as aluminum, brass,copper, lead and tin, magnesium, zinc, steel, titanium, etc.

The arc 1001 after linear extrusion may have complex cross-sections. Forexample, the linear arc 1001 may comprise a flat top with wing featuresand a circular pipe-line channel. The linear arc formed after linearextrusion may comprise the wing features of various shape. The wingfeature may or may not be a flat. The wing feature may be formed withfine features such as steps, grooves, ducts, slots, etc. The channelformed after the linear extrusion may or may not be trimmed to have astraight through hollow shape. The hollow portion may be provided alongthe entire length of the arc or a portion of the length. Thecross-section of the prismatic linear arc formed after linear extrusionmay not be changed during further deformation process.

In some embodiments, deformation operations may be performed to causebending and twisting of the prismatic linear arc. A metal extrusion maycomprise single or multiple bends and/or twists to form into the desiredshape. As shown in FIG. 10, the prismatic linear arc may have a helicaltwist along its length 1011. This helical twist may be formed by pipeand tube twisting manufacturing process. After the helical twistprocess, the cross-section of the arc may be unchanged remaining aconstant area along the length of arc, however the orientation angle maybe changed. For example, the arc 1001 may be twisted clockwise directionto have a helical twist shape 1011. The twist may be in any directionwith any twisting rate/angle. For instance, the twist may be incounter-clockwise direction with a different twisting rate. In somecases, the helix twisting rate has a constant rate of change along thelength. In other cases, the helix twisting rate is variable along thelength.

The formed prismatic linear arc may be further deformed in order to meetthe shape and structural requirements. In some embodiments, thedeformation may include bending and/or twisting the prismatic linear arcat any orientation to any degree. The various combinations of bendingand twisting may allow the arc form into designed shape. The variouscombinations of bending and twisting may also induce keying features asdescribed elsewhere herein. In some embodiments, manufacturing processsuch as tube and pipe bending may be included in the arc formingprocess.

FIG. 11 illustrates an exemplary arc forming apparatus 1100, inaccordance with embodiments. In some embodiments, the arc formingapparatus may include a tube and pipe bending machine. A prismaticlinear arc can be deformed using the bending machine to create a varietyof single or multiple bends and/or twists to shape the workpiece intothe desired form. The bending process may be press bending, rotary drawbending, freeform-bending, three-roll-push bending, etc. The deformationprocess may or may not involve heat-induction. The manufacturing processmay be standard automation machinery that is known to those skilled inthe art.

In some embodiments, the prismatic linear arc with variouscross-sections can be bent and twisted. As previously described, thecross-section may be a complex shape formed by extrusion process. In theexample as shown in FIG. 11, the workpiece 1103 may be guided to travelthrough a base die 1107 and a bend die 1109. The workpiece 1103 may bean extrusion formed prismatic linear arc. The workpiece may be astraight stock. The workpiece may be a hollow tube with variouscross-section shapes. The workpiece 1103 may be caused to move throughthe base die and bend die by any suitable driving mechanism 1101. Thedriving mechanism can be, for example, a mechanical force to push theworkpiece against the die or a driving force to draw the workpiecethrough the process.

In some embodiments, customization of the tool may be required such asdesign of the die and mandrel 1105 in order to fit the extruded shape ofthe linear arc. The shape and geometry of the die and mandrel may bedesigned to match the shape, size and geometry of the extruded arc. Forexample, a metal extrusion comprising a D-shaped conduit may require amatching D-shaped mandrel. The mandrel 1105 may be inserted into the arcwhile the arc is being bent to give extra support to reduce wrinklingand breaking of the arc during the process. The mandrel may be insertedinto a conduit of the arc, or the hollow portion of the arc. The shapeof the mandrel may be designed in order to be able to fit into a hollowportion of the arc. The mandrel may be single piece or multiple pieces.

The workpiece 1101 can be bent and twisted in multiple directions andangles. For example, a single bend may cause the arc to form an elbowshape range from 1 to 90 degree. The bending and twisting may includetwo-dimensional bends and three-dimensional bends such that the formedarc may have a two-dimensional shape or a three-dimensional shape. Insome embodiments, a bend head 1111 may be used to alter the bendingangle, orientation or direction of the workpiece. The bend head 1111 canhave various orientations with respect to an extrusion axis of theworkpiece. The orientation of the bend head guides a bending directionas the workpiece move through the bend head. For example, as theworkpiece travels through the bend head, it can be bent and twisted inthe clockwise or counterclockwise direction, diverted up, down, to theleft or right, or in any combination of the directions. The bend head1111 may be actuated to change orientations while the workpiece movessuch that any desired bend or twist may be formed. The orientation ofthe bend head 1111 may be adjusted manually or automatically. The bendhead 1111 may be programmed to rotate and move in any direction to anydegree to alter the workpiece into the desired shape. In someembodiments, the orientation and alteration rate may determine thebending and twisting direction and degree. In some embodiments, an arcmay be formed by passing through one bend head. Alternatively, an arcmay be formed by passing through multiple bend heads.

FIG. 12 shows more examples about the bending and twisting process, inaccordance with embodiments. The formed arc 1200 is formed with a singlebend 1203. In some embodiments, the arc may comprise multiple bends. Insome embodiments, the dimension of the workpiece 1201 may be preciselycontrolled. For example, the location of the bend, degree of the bendand orientation of the bend can be precisely controlled. In someembodiments, the bending and twisting may be repeated along the lengthof the arc. The bending and twisting may be superimposed. In someembodiments, the bending and twisting may be performed through singleprocess. In some embodiments, the bending and twisting may be performedconcurrently. Alternatively, bending and twisting may occur in a serialmanner.

In some embodiments, mandrels may be used in the bending and twistingprocess. The mandrel may be used to provide support to the workpiecewhile it is driven through the bending process to reduce wrinkling andbreaking of the workpiece. The mandrel may be inserted into a conduit ofthe arc, or the hollow portion of the arc. The mandrel 1207 may beinserted into the extrusion formed arc 1205 prior to the bending process1210. The mandrel may be temporarily inserted into the arc and removedafter the process.

The shape of the mandrel may be designed in order to be able to fit intoa hollow portion of the arc. The mandrel may be single piece or multiplepieces. The radius geometry of the mandrel may be designed such that itcan fit into the channel of the extruded arc. In some embodiments, themandrel may be designed to fit into a hollow portion between the wingfeature and an external surface of the channel to provide extra support.

The mandrel 1211 may be used to guide the arc during the bending process1220. In some embodiments, the mandrel 1211 may comprise nose features1213 to provide extra support and guidance at the bending alteration.The nose feature 1213 may ensure the cross-section of the workpieceremain unchanged in the zone of alteration by conform to the curvatureof the bending zone. The use of mandrel may prevent collapsing of thearc wall, creasing and wrinkles ovalization, and other defects duringstress.

In some embodiments, the arc member may comprise wing features. The wingfeatures may be formed by extrusion and bending process. In someembodiments, the wing feature formed after the linear extrusion asdescribed in FIG. 10 and bending and twisting along the length of thearc member as described in FIG. 11 may be further deformed to alter thecross-section shape of the arc member. FIG. 13 illustrates exemplarybending wing feature, in accordance with embodiments.

The wing feature can be bent after a prismatic linear arc formed byextrusion. For example, the wing feature 1301 may be bent downwards,upwards, symmetrically, asymmetrically to form desired shape. The wingfeature may be bent to alter a cross-section shape of the arc member.The altered cross-section may be constant along the length. Thecross-section may be variable along the length. For instance, the wingfeature may be bent to a degree at one end 1301 while remain a flat top(unchanged) at the other end 1305. The flexibility of bending the wingfeature into various shapes may provide unique keying features asdescribed elsewhere herein. For instance, the two ends with dissimilarbending shapes may be used to prevent errors during assembly.

FIGS. 14A-B illustrate an exemplary dynamic die 1400 that can deformdifferent portions of a metal extrusion in different directions. Dynamicdie 1400 can include a first die component 1401, a second die component1403, a third die component 1405, a fourth die component 1407, a fifthdie component 1409, and a sixth die component 1411. The die componentscan be, for example, solid metal components (e.g., plates, blocks),rollers, mechanical presses, etc. The die components can be configuredto attach to actuators (not shown) and to move independently of eachother. In this way, for example, the different die components of dynamicdie 1400 can deform different portions of a metal extrusion in differentdirections.

FIGS. 14A-B also show dynamic die 1400 can accept a metal extrusion1413. Metal extrusion 1413 can include a first structure 1415 connectedto a second structure 1417. FIG. 14A shows metal extrusion 1413 when themetal extrusion is a blank, that is, a structure prior to deformation bydynamic die 1400. In this example, metal extrusion can be a blank thatwill be deformed into arc member 320 of FIG. 3. Therefore, firststructure 1415 can be an elongated cavity like elongated cavity 323, andsecond structure 1417 can be a structure with an elongated surface likewing feature 321. Second structure 1417 can include a first portion 1419and a second portion 1421. The first and second portions can, forexample, correspond to separate wings of the wing feature of secondstructure 1417.

As can be seen in FIG. 14A, the configuration of the die componentsdefines a die cross-section that conforms to the cross-section of metalextrusion 1413 prior to deformation (i.e., when the metal extrusion is ablank).

Metal extrusion 1413 can be moved through dynamic die 1400 (e.g., movedinto the page as viewed in FIGS. 14A-B) while the die components aremoved to deform various portions of the metal extrusion. FIG. 14B showsan example movement of dynamic die 1400. Specifically, first and fifthdie components 1401 and 1409 can be rotated differently (e.g., one in aclockwise direction and the other in a counterclockwise direction) suchthat first and second portions 1419 and 1421 are bent downward towardfirst structure 1415. Second and fourth die components 1403 and 1407 canbe rotated and translated to conform to the curve of second structure1417 as the second structure bends, and third die component 1405 can betranslated to conform to the curve as well. The position of sixth diecomponent 1411 can remain fixed relative to the other die components. Inthis way, for example, dynamic die 1400 can deform different portions ofmetal extrusion 1413 in different directions, thereby creating a curvedelongated surface 1423.

As can be seen in FIG. 14B, the configuration of the die componentsdefines a die cross-section that conforms to the cross-section of metalextrusion 1413 after the deformation operation. The shape of the diecross-section prior to the deformation operation (i.e., shown in FIG.14A) is different than the die cross-section after the deformationoperation (i.e., shown in FIG. 14B).

In the example, the die components of dynamic die 1400 can be arrangedroughly in the same plane (i.e., the plane of the drawing page). In thiscase, dynamic die 1400 can be implemented with a base die, such as basedie 1107 of FIG. 11, in order to bend metal extrusion 1413 into the arcshape of arc member 320, for example. In this regard, dynamic die 1400can be implemented as bending die 1109 in arc forming apparatus 1100. Inthis way, for example, dynamic die 1400 can deform a blank metalextrusion into arc member 320.

FIG. 15 illustrates an exemplary layered dynamic die 1500. Layereddynamic die 1500 can include die components arranged in differentlayers, such as a first die layer 1501, a second die layer 1503, a thirddie layer 1505, etc., such that the die layers overlap. In this way, forexample, layered dynamic die 1500 may be implemented to createstructures such as arc member 320 of FIG. 3 without needing a base diesuch as base die 1107 of FIG. 11 to form the arc.

FIGS. 16A-F illustrate exemplary layers of a layered dynamic die, suchas dynamic die 1500. In the example of FIGS. 16A-F, the layered dynamicdie can deform a blank metal extrusion in the same way as dynamic die1400 of FIGS. 14A-B, as will be understood from the illustrations ofFIGS. 16A-F.

FIG. 16A illustrates a first layer 1601, which is the first layer theblank passes through during the deformation operation of the dynamicdie. In this case, first layer 1601 can include a single plate of metalformed into a first die 1602 of layered dynamic die 1600. First die 1602can conform to a lower surface 1603 of a metal extrusion 1605. First die1602 can be configured to connected to actuators (not shown) that canmove the first die in translational directions 1607 and rotationaldirections 1609. Movement in translational directions 1607 androtational directions 1609 can be independent of the movements of otherlayers of layered dynamic die 1500. In this regard, although FIG. 15illustrates the layers as abutting each other, the dies in consecutivelayers can be arranged with space in between to allow for independentrotational movements of the dies in the consecutive layers.

FIG. 16B illustrates a second layer 1611 that includes a base 1613 thatcan support a second die 1615. Second die 1615 can conform to a firstportion 1617 of metal extrusion 1605. Second die 1615 can include openspace around the remaining portion of metal extrusion 1605. Second die1615 can include teeth 1619 around a perimeter of the second die. Ascrew 1621 can engage teeth 1619, and the screw can be connected to amotor 1623 that can turn the screw and thereby rotate second die 1615 toeffectuate a bending deformation of first portion 1617.

Similarly, FIG. 16C illustrates a third layer 1625 that includes a base1627 that can support a third die 1629. Third die 1629 can conform to asecond portion 1631 of metal extrusion 1605. Third die 1629 can includeopen space around the remaining portion of metal extrusion 1605. Thirddie 1629 can include teeth 1633 around a perimeter of the third die. Ascrew 1635 can engage teeth 1633, and the screw can be connected to amotor 1637 that can turn the screw and thereby rotate third die 1629 toeffectuate a bending deformation of second portion 1631.

FIG. 16D illustrates a fourth layer 1639 that includes a base 1640supporting a fourth die 1641. Fourth die 1641 can be connected to anactuator 1643 that can move the fourth die in a translational directionup and down to conform to a top surface of metal extrusion 1605.

FIG. 16E illustrates a fifth layer 1645 that includes a base 1647supporting a fifth die 1649. Fifth die 1649 can be connected to anactuator 1651 that can move the fifth die in a translational androtational direction to conform to another portion of the top surface ofmetal extrusion 1605.

Likewise, FIG. 16F illustrates a sixth layer 1653 that includes a base1555 supporting a sixth die 1657. Sixth die 1657 can be connected to anactuator 1659 that can move the sixth die in a translational androtational direction to conform to another portion of the top surface ofmetal extrusion 1605.

The movements of the various motors, actuators, etc., that move thevarious dies of layered dynamic die 1500 can be performed independentlyof each other. In this way, for example, different portions of metalextrusion 1605 can be deformed in different directions.

In the example of FIGS. 16A-F, each die layer includes only a singledie. FIG. 17 illustrates another configuration of an exemplary layer ofa layered dynamic die, in which multiple dies are included in a singlelayer.

FIG. 17 illustrates an exemplary die layer 1700 including multiple dies.In various embodiments, die layer 1700 can be substituted for second andthird die layers 1611 and 1625 in the previous example of FIGS. 16A-F.Die layer 1700 can include a base 1701 that supports a left die 1703 anda right die 1705, which can both include teeth 1707. A left screw 1709and left motor 1711 can engage teeth 1707 of left die 1703 to rotate theleft die, and a right screw 1713 and a right motor 1715 can engage theteeth of right die 1705 to rotate the right die. In this example,because the dies are smaller than the corresponding dies in the previousexample, multiple dies can be arranged in a single layer. Also, is notedthat centers of rotation 1717 of left die 1703 and right die 1705 can beadjusted more easily due to the smaller size of the dies.

FIG. 18 is a flowchart illustrating an example method of deforming ametal extrusion in different directions. A metal extrusion can beaccepted (1801) into a die, such as the dynamic dies described above.The metal extrusion can be similar to those described above in theexamples of FIGS. 3, 5, 10, and 13. In other words, the metal extrusioncan a first structure and a second structure and can have a length. Thefirst structure can include an elongated cavity along the length of themetal extrusion. The second structure can include an elongated surfacealong the length of the metal extrusion. The elongated surface can bearranged away from the first structure and overlapping at least aportion of the first structure, and the first and second structures canbe connected along the length of the metal extrusion.

The first structure can be deformed (1802) in a first direction. Forexample, a base die can be used in combination with a dynamic die suchas dynamic die 1400 of FIGS. 14A-B to deform the first structure into anarc, or layered dynamic die 1500 can be used to deform the firststructure into an arc. The second structure can be deformed (1803) in asecond direction different than the first direction. In FIGS. 14A-B, forexample, first and fifth die components 1401 and 1409 can deform firstand second portions 1419 and 1421, respectively, of metal extrusion1413. In FIGS. 16A-F, for example, second and third dies 1615 and 1629can deform first and second portions 1617 and 1631, respectively, ofmetal extrusion 1605.

The arcs and nodes can be used in vehicle structures such as vehiclechassis. The vehicle chassis may be used for any type of vehicles,including but limited to an aerial vehicle, a vehicle traversing waterbody, a land vehicle, or any other suitable type of vehicles. Vehiclesmay comprise arc and nodes based structures. In some embodiments, thearc and nodes based structure may be used to provide support tonon-structural components such as body panels. The forma and shape ofbody panels may be determined by non-structural factors that includeaerodynamics, styling, visibility, safety, and various others. Thepresent invention may be provided to allow the design and manufacture ofa vehicle meet multiple requirements that may or may not be conflictingwith each other.

The arcs and nodes based structures may provide structural support aswell as mating interface to the non-structural components. In someembodiments, the non-structural components may have a shape, externalsurface, topology or configuration that require the supporting arcs andnodes based structure comprise a mating shape. In some embodiments, thearcs and nodes based structure may provide any desired shape to meet theshape requirement, such as a smooth transition on an external surface ofthe vehicle.

The non-structural components may include but not limited to glasswindow, doors, sills, body panels, and various components as describedelsewhere herein. FIG. 19 shows examples of arcs and nodes based roofstructure, in accordance with embodiments.

In the example, the roof structure may comprise multiple nodes 1901,1903 and multiple arcs 1905, 1907, 1909. The arcs and nodes structuremay be provided to interface with a non-structural component such as aroof panel (not shown) to form a roof structure. The nodes 1915 maycomprise a D-shaped channel and connecting features 1911, 1913 to matewith the corresponding arcs 1907, 1905 in a unique configuration. Thenodes as shown in the example are located at the corner. The nodes andarcs may be connected to form a frame to accept a panel or a glass roofas described later herein. The external shape of the nodes and arcs mayform a smooth surface to be mated with other components of the vehicle.The nodes and arcs structure can be the same nodes and arcs structure asdescribed elsewhere herein.

FIG. 20 shows an example of a metal extrusion and node structureconnected to panels, in accordance with embodiments. The node 2003 andarc 2007 may correspond to the node 1903 and arc 1909 in FIG. 19. Theconnected node and arc structure may be configured to connect to twopanels 2001, 2011. The panels may have a curved surface. In the roofstructure example, the panel may be made of glass, sheet metal or otheropaque material. In some embodiments, adhesives may be used at acontacting interface between the panels and the arcs wing features 2009,2005. In some embodiments, the adhesives may also be used between thepanels and the nodes extrusion features, such as the extrusion featuredescribed in FIG. 4. Adhesives may be applied to any contactinginterface between the arcs and nodes structure and the panels. Anycoupling means may be used to connect the arcs and nodes structure topanels as described elsewhere herein. Both sides of the arc member maybe connected to panels. Alternatively, either side of the arc member maybe connected to a panel. In other embodiments, the arc may providesupport to panels not through the wing feature such as the arc 2013 inFIG. 20. In this case, adhesives may be applied between the top of arc2013 and the overhead glass roof 2015.

In the roof structure example, the curved panel 2015 may be a glass roofintegrated into the arc and nodes based structure. The arcs and nodesstructure 2019, 2017, 2013, 2003, 2007 may correspond to the structuredescribed in FIG. 19. The arcs and nodes structure may be designed andmanufactured to form a continuous smooth surface together with the glassroof 2015. The external surface of the formed roof structure may provideaerodynamic and styling advantages. The external surface of the formedroof structure may be constructed by the facets from the glass top 2015,the top surface of the wing features of the arcs 2017, 2007 and theextrusion features of the nodes 2019, 2003.

The arcs and nodes structures may be included in vehicle chassis. Thevehicle chassis may support various components of the vehicle as well asdynamic and static loads. In some embodiments, the loads may include forexample, the weight of the vehicle plus the passengers and cargo,vertical, torsional, twisting forces induced by travelling over unevenroad surface, transverse lateral forces cause by road conditions, sidewinds, steering through turns, propulsion torque from the engine andtransmission, longitudinal tensile forces from starting andacceleration, compression from braking, sudden impacts from collisions,and the like. The vehicle chassis may provide support to components forvarious purposes such as aerodynamic efficiency, shielding from noiseand vibration, styling and appearance, visibility and safety, etc. Thepresent invention provides a metal extrusion and nodes based structurethat allows optimized tradeoffs between the demands of the variousfactors as described previously.

FIG. 21 illustrates an exemplary vehicle 2100 based on the nodes andarcs structures, in accordance with embodiments. Multiple arcs and nodesstructures may be included and weaved into the vehicle's design to formthe chassis and body. The vehicle chassis may include connecting tubesand arcs connected by nodes (a.k.a. joints). The vehicle structure maybe a frame. The vehicle structure may be a body. The frame and body maybe three-dimensional. The arcs and nodes structures may be integratedinto the vehicle structure at multiple levels. For example, arcs andnodes based structure may be pre-assembled as a subassembly beforeintegrated into the vehicle structure. In some cases, the arcs and nodesstructure are included to connect one or more body panels to the vehicleframe.

A vehicle chassis may form the framework of a vehicle. A vehicle chassismay provide the structure for placement of body panels of a vehicle,where body panels may be door panels, roof panels, floor panels, or anyother panels forming the vehicle enclosure. Furthermore the chassis maybe the structural support for the wheels, drive train, engine block,electrical components, heating and cooling systems, seats, or storagespace. A vehicle may be a passenger vehicle capable of carrying at leastabout 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more,7 or more, 8 or more, ten or more, twenty or more, or thirty or morepassengers. Examples of vehicles may include, but are not limited tosedans, trucks, buses, vans, minivans, station wagons, RVs, trailers,tractors, go-carts, automobiles, trains, or motorcycles, boats,spacecraft, or airplanes (e.g., winged aircraft, rotorcraft, gliders,lighter-than-air aerial vehicles). The vehicles may be land-basedvehicles, aerial vehicles, water-based vehicles, or space-basedvehicles. Any description herein of any type of vehicle or vehiclechassis may apply to any other type of vehicle or vehicle chassis. Thevehicle chassis may provide a form factor that matches the form factorof the type of vehicle. Depending on the type of vehicle, the vehiclechassis may have varying configurations. The vehicle chassis may havevarying levels of complexity. In some instances, a three-dimensionalspace frame may be provided that may provide an outer framework for thevehicle. The outer framework may be configured to accept body panels toform a three-dimensional enclosure. Optionally, inner supports orcomponents may be provided. The inner supports or components can beconnected to the space frame through connection to the one or more jointmembers or arc members of the space frame. Different layouts ofmulti-port nodes, arcs and connecting tubes may be provided toaccommodate different vehicle chassis configurations. In some cases, aset of nodes can be arranged to form a single unique chassis design.Alternatively, at least a subset of the set of nodes can be used to forma plurality of chassis designs. In some cases, at least a subset ofnodes in a set of nodes can be assembled into a first chassis design andthen disassembled and reused to form a second chassis design. The firstchassis design and the second chassis design can be the same or they canbe different. Nodes may be able to support tubes and arcs in a two orthree-dimensional plane. The tubes and arcs connected to a multi-prongnode may be provided in a three-dimensional fashion and may span threeorthogonal axes. In alternate embodiments, some nodes may connect tubesand arcs that may share a two-dimensional plane. In some cases, thejoint member can be configured to connect two or more tubes wherein eachtube in the two or more tubes has a longitudinal axis along a differentplane. The different planes can be intersection planes. In someembodiments, a single joint member can be configured to connect tubesand arcs using separate ports.

FIG. 22 shows examples of arcs and nodes based structure used in avehicle, in accordance with embodiments. The vehicle in FIG. 22 maycorrespond to the vehicle in FIG. 21. A left half of the cross-sectionview of the vehicle is shown in scenario A. The window glass 2201 ismounted atop the door panel 2205. A metal extrusion 2203 is connected tothe door panel 2205 to provide support. The arc 2203 may be connectedwith two nodes (not shown) at the distal ends such that the arc may bepart of a vehicle frame. The arc 2203 has a curved profile mated withthe external surface of the door panel 2205 such that a smooth cornermay be provided. Arc 2207 is provided between the door panel 2205 andstep panel 2213. The arc 2207 connects the two panels arranged in anangle while provides a smooth transition on the external surface. Theprofile of the arc 2207 is substantially concave whereas the arc 2211for connecting the step panel 2209 and the rocker panel 2217 issubstantially convex. The arcs 2211, 2207 together may providestructural support to the step panel 2209 so that the step panel may beable to support the weight of a standing people. The arc 2215 is used toprovide support to the rocker panel 2213 and the skid plate 2217. Aperspective view of the same structure is provided in scenario B. Asdescribed previously, various connecting means may be used to connectthe arcs to the panels. The connecting means may be selected based onthe materials of the components, the shape, required coupling strengthand/or assembly requirements, etc. In some embodiments, differentconnecting means may be used for the same arc member. For example, thearc 2215 may have a mating surface such as one side of the wing featureto be fastened to the rocker panel 2213. Examples of mechanicalfastening means may include but not limited to screws, bolts, nuts,rivets, interlocks, or clamps. In the meantime, the other side of thewing feature of arc 2215 may be connected to the skid plate 2217 usingadhesives.

In some embodiments, certain parts/sections of the vehicle may beattached using fastening techniques, while other parts are attachedusing adhesives. Alternatively or additionally, nodes and arcs may beattached using adhesives within certain sections, while fasteningtechniques are used for inter-section connections. For example, within areplaceable section (e.g., a crumple zone) nodes and arcs may beattached together using adhesives, while the replaceable section may beattached to other parts of the vehicle using fastening techniques suchthat when the replaceable part is destroyed in a crash, it can bereplaced by a new part easily. A metal extrusion may have one end gluedto an integral one-piece node whereas the other end glued to anothernode or node component, which may permit a bolting section with anothernode component. A node may be glued to a metal extrusion at one acceptorport and glued to another tube at another acceptor port, and may or maynot be formed of multiple node components that may be fastened together.

When using adhesives to attach the one or more arcs to the panels, itcan reduce the overall weight of the vehicle. However, when a certainpart of the vehicle needs to be replaced due to a crash or a componentfailure, it may be difficult to replace the certain part only withoutabandoning the entire structure, or to remove the certain part alone.Using a technique where arcs are attached to panels with aid of one ormore fasteners may facilitate disassembly of the vehicle chassis asneeded. For instance, one or more fasteners may permit the arcs to beremovable relative to one another by unfastening the arcs. Then, theportion of the vehicle body that needs to be replaced can be swapped infor a new piece that can be fastened to the existing vehicle structure.For example, when a certain part of the vehicle needs to be replaced,the corresponding arcs and nodes may be easily disassembled, and a newreplacement part may be fastened (e.g., bolted, screwed, riveted,clamped, interlocked) to the original structure. This may provide a widerange of flexibility, and the portions of the vehicle chassis may rangefrom a single piece to whole sections of the vehicle. For instance, if asection of a vehicle crumpled on impact, the entire section may bedisassembled from the vehicle chassis and replaced with a new sectionwhich is undamaged. In some instances, such section of a vehicle may benon-structural such as a window structure, a roof structure, a doorstructure, or a structural module such as a chassis module, a chassissub-structure, a chassis sub-assembly, or any other part of a vehicle asdiscussed herein. The new section may be pre-assembled and then attachedto the vehicle body at the connection points, or may be assembledpiecemeal on the existing vehicle chassis and body. Such flexibility mayalso allow easy upgrades or modifications to the vehicle.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these exemplary embodiments presented throughout thisdisclosure will be readily apparent to those skilled in the art. Thus,the claims are not intended to be limited to the exemplary embodimentspresented throughout the disclosure, but are to be accorded the fullscope consistent with the language claims. All structural and functionalequivalents to the elements of the exemplary embodiments describedthroughout this disclosure that are known or later come to be known tothose of ordinary skill in the art are intended to be encompassed by theclaims. Moreover, nothing disclosed herein is intended to be dedicatedto the public regardless of whether such disclosure is explicitlyrecited in the claims. No claim element is to be construed under theprovisions of 35 U.S.C. § 112(f), or analogous law in applicablejurisdictions, unless the element is expressly recited using the phrase“means for” or, in the case of a method claim, the element is recitedusing the phrase “step for.”

1. A method of manufacturing a structure, the method comprising:accepting a metal extrusion, the metal extrusion including a firststructure and a second structure, the metal extrusion having a length,wherein the first structure includes an elongated cavity along thelength of the metal extrusion, and the second structure includes anelongated surface along the length of the metal extrusion, the elongatedsurface being arranged away from the first structure and overlapping atleast a portion of the first structure, the first and second structuresbeing connected along the length of the metal extrusion; deforming thefirst structure in a first direction; and deforming the second structurein a second direction different than the first direction.
 2. The methodof claim 1, wherein the first and second structures are deformed suchthat a shape of a first cross-section of the metal extrusion at a firstlocation along a length of the metal extrusion is different than a shapeof a second cross-section of the metal extrusion at a second locationalong the length of the metal extrusion.
 3. The method of claim 1,wherein the first direction is a direction that is transverse to thelength of the metal extrusion, and the second direction is a directionof rotation around a direction parallel to a length of the elongatedcavity.
 4. A die for deforming a metal extrusion, the die comprising: afirst die component that deforms a first portion of the metal extrusionin a first direction; and a second die component that deforms a secondportion of the metal extrusion in a second direction different than thefirst direction.
 5. The die of claim 4, wherein the metal extrusion hasa length, and the first and second portions are deformed such that ashape of a first cross-section of the metal extrusion at a firstlocation along the length of the metal extrusion is different than ashape of a second cross-section of the metal extrusion at a secondlocation along the length of the metal extrusion.
 6. The die of claim 4,wherein the metal extrusion has a length, the first portion includes anelongated cavity along the length of the metal extrusion, the firstdirection is a direction that is transverse to the length of the metalextrusion, and the second direction is a direction of rotation around adirection parallel to a length of the elongated cavity.
 7. The die ofclaim 4, wherein the first die component and the second die componentdefine a shape of portion of a die cross-section, and the deforming bythe first and second die components causes the shape of the portion ofthe die cross-section to change.
 8. The die of claim 4, wherein thefirst die component is arranged in a first layer, and the second diecomponent is arranged in a second layer that overlaps the first layer.